Abstract: EJ.00002 : Frozen fronts in cellular flows

Authors:

Mollie Schwartz
(Bucknell University)

Tom Solomon
(Bucknell University)

We present experiments showing that cellular flows often freeze
the motion of chemical fronts in the presence of an opposing
uniform wind. Fronts pin to the vortex structure in a chain of
counter-rotating vortices for a wide range of imposed wind speeds
that grows nonlinearly with the strength of the underlying
vorticity. The same phenomenon is observed in a two-dimensional,
spatially-disordered array of vortices, indicating that the
ability to pin fronts is a general property of vortices. We
further investigate the strength of the pinning with the addition
of a time-periodic (oscillatory) wind, introducing chaotic
advection and potential effects of mode-locking. These results
demonstrate that any general theory of
advection-reaction-diffusion dynamics will have to account for the
tendency of cellular structures to pin fronts.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.DFD.EJ.2